International ozone Layer Protection Day, how much do you know about this festival?

China Meteorological News Today (September 16) is the international ozone Layer Protection day. The ozone layer is a relatively high concentration of ozone in the stratosphere of the atmosphere, and its main role is to absorb short-wave ultraviolet rays. As human activity intensifies, the ozone layer on the surface of the earth is seriously void and the ultraviolet radiation is enhanced, which will have a very negative impact on human beings and the environment in which they live. The destruction of the ozone layer will disrupt the complex food chain in the ecosystem, leading to the extinction of some major biological species. The destruction of the ozone layer could also reduce the production of two-thirds of the Earth's crops, leading to a food crisis. Increased ultraviolet radiation will lead to global warming.

What is the ozone layer?
The ozone layer refers to a relatively high concentration of ozone in the stratosphere of the atmosphere, and its main role is to absorb short-wave ultraviolet rays. Ozone in the atmosphere is mainly used to attack the oxygen of two atoms by ultraviolet light, dividing it into two atoms, and then each atom and the oxygen without splitting are combined into ozone. Ozone molecule is unstable, ultraviolet radiation is divided into oxygen molecules and oxygen atoms, forming a continuous process of ozone oxygen cycle, so that the ozone layer.
The ozone layer in nature is mostly distributed at altitudes of 20 to 50-kilometer. The ozone layer absorbs more than 99% of the sun's ultraviolet rays that are harmful to humans, protecting life on Earth from short-wave ultraviolet rays. Therefore, the ozone layer is known as the Earth's biological survival and reproduction of the umbrella.

The role of the ozone layer
1. Earth's biological umbrella
The ozone layer absorbs sunlight. The ozone layer blocks ultraviolet rays, protecting humans and animals and plants on Earth from the damage of short-wave ultraviolet rays. So the ozone layer protects the Earth's creatures from survival and reproduction.
2. Created the atmosphere of the stratosphere
Ozone absorbs ultraviolet rays from sunlight and converts them into heat to heat the atmosphere, because of this effect, the atmosphere temperature structure in the height of about 50-kilometer has a peak, the Earth over the 15~50 kilometer there is a warming layer. It is because of ozone that there is a stratospheric existence. There is no ozone or oxygen on the planet outside the Earth, so there is no stratosphere. The temperature structure of the atmosphere has an important effect on the circulation of the atmosphere, and the cause of this phenomenon is also the high distribution of ozone.

Effects of the ozone layer
after the depletion of the ozone layer, the ability to absorb ultraviolet radiation greatly weakened, resulting in the arrival of the surface of the Earth's ultraviolet B significantly increased, to the human health and ecological environment to bring many hazards, has been widely concerned about the main human health, terrestrial plants, aquatic ecosystems, biochemical cycle , materials, and the effects of atmospheric composition and air quality in the troposphere.
1. Effects on health
The increase in UV-B in sunlight has a serious detrimental effect on human health. Potential risks include the initiation and exacerbation of eye diseases, skin cancer and infectious diseases. Studies have shown that long-term exposure to strong ultraviolet radiation, will lead to the body's immune system function, the body's ability to resist disease decline.
2. Effects on plants
plant growth is directly affected by UV-B radiation, and different species of plants, and even plants of different cultivars of the same species, react differently to UV-B. In agricultural production, it is necessary to plant varieties that tolerate UV-B radiation and to cultivate new varieties at the same time. For forests and grasslands, it is possible to change the composition of species, which in turn affects the distribution of biodiversity in different ecosystems.
3. Impact on ecology
Researchers have measured the increase in the number of UV-B radiation in Antarctica and its penetrating water, and there is sufficient evidence that the natural phytoplankton community is directly related to changes in ozone.
4. Effects on cycles
The increase in ultraviolet rays of sunlight affects biogeochemical cycles of land and water, thus altering the cycle of important substances in the Earth's various circles in the Earth-atmosphere, such as greenhouse gases and other trace gases that have an important role in chemical reactions, Including carbon dioxide, carbon monoxide, oxygen sulfide and so on. These potential changes will have an impact on the interaction between the biosphere and the atmospheric circle.
Terrestrial ecosystems: Increased ultraviolet rays can change plant formation and decomposition, thereby altering the absorption and release of important gases in the atmosphere.
Aquatic ecosystems: Sunlight ultraviolet rays directly cause the effects of UV-B on carbon cycling, nitrogen cycling and sulfur cycling in aquatic ecosystems.
5. Impact on materials
The increase in ultraviolet radiation due to stratospheric ozone depletion will accelerate the degradation and deterioration of materials used in construction, spraying, packaging and wire and cable, especially polymer materials. Especially in hot and sunny tropical areas, this destructive effect is even more serious. The damage caused by this destructive effect is estimated to reach billions of dollars a year worldwide. Whether it is artificial polymers, natural polymers and other materials will be adversely affected.

Protect the ozone layer from me
1. Products to be purchased with a "care for the ozone layer" or "CFC-free" logo are used to reduce the use of CFCs (paper and plastic products made from foaming agents).
2. Minimize the use of cold, heating machine, save electricity, reasonable treatment of waste refrigerators and electrical appliances, to form a daily less open a car, hot days when the air-conditioning up 1 ℃.
3. More use of showers can effectively reduce the habit of energy consumption.
4. Learn and publicize knowledge on the protection of the ozone Layer and participate actively in the ozone layer protection activities.

The origin of international ozone Layer Protection Day
To arouse public awareness of environmental protection, January 23, 1995 the United Nations General Assembly decided that September 16 of the year is the International Day for the protection of the Ozone layer (Internationalday for the preservation of the Ozone Layer), requiring all States parties to comply with the The Montreal Protocol on Substances that Deplete the Ozone Layer and the objectives of its amendments, take concrete action to commemorate this day. In the face of the severe damage to the ozone layer, the international community, in coordination with the United Nations Environment Programme (UNEP), established the Vienna Convention for the Protection of the Ozone Layer in 1985, established the principles for international cooperation in the protection of the ozone layer, and in 1987 the Montreal Protocol on Substances that Deplete the Ozone Layer Established the Global Framework for international cooperation for the protection of the ozone layer.